Brief Description of the Prior Art
One method of feeding livestock which has found a high degree of acceptance to farmers is the loading of the feed stock into an elongated flexible tube made of weather resistant plastic, and feeding from this bag until the feed is exhausted. Several types of machines have been provided for loading the comminuted feed stock into the bags preparatory to feeding the livestock from the bag over a period of several months. Such machines, in general, include a housing which defines a compacting and forming chamber, and a throat or passageway communicating with this chamber. Upstream from the throat or passageway is a zone in which a cylindrical drum is located. This drum has a plurality of radially projecting teeth or tines, and is rotatably mounted in the housing of the apparatus. It functions to force the feed stock into the compacting and shaping chamber, and from that chamber, into the flexible bag. Generally a plurality of fixed stripper fingers are provided which cooperate with the teeth carried on the drum to clean these teeth as the teeth are rotated through the fixed fingers. In at least one type of silage bagging machine which has been proposed, an auger or screw conveyor is mounted in the trough into which the raw silage or feed stock is dumped, and this auger functions to distribute the feed in an even manner as it is fed to the teeth-carrying drum.
In machines of the type described, the elongated flexible agricultural bag is paid out from the rear end of the machine as the filling of the bag progresses. The apparatus which compacts the feed and forces it into the flexible bag is then allowed to move slowly away from the bag in a controlled fashion by means of a braking system which controls the rate at which the feeding apparatus moves away from the progressively filling bag.
These horizontally expansible, flexible feed stock storage bags have become widely used in some dairy and beef cattle areas as an alternative to permanent storage structures, such as barns or silos.
One type of apparatus which is currently in limited use for loading silage into such flexible bags is disclosed in U.S. Pat. No. 4,046,069 to Eggenmuller et al. In the Eggenmuller et al patent, a loading channel supports the forward portion of an unfilled bag, and guides the feed stock from a tine-carrying grinding drum which carries spirally arrayed tines which project radially from the outer periphery of the drum.
The feed stock is initially fed into a hopper of the apparatus. There it is acted on by a reciprocating member which forces the feed stock into the tine-carrying drum, and the teeth of this drum then force the stock through a forming chamber into a storage bag. A gate or backstop is held against the closed end of the storage bag with cables connected from the backstop to a drum carried on the Eggenmuller apparatus. A brake arrangement is used in conjunction with the drum to apply controlled and adjustable, controlled tension to the cables, so that during the filling of the storage bag, the resistance offered by the braking force will be overcome and the apparatus will slowly move away from the gate or backstop, allowing a new portion of the bag to be continuously filled.
In Johnson et al U.S. Pat. No. 4,337,805, an apparatus which resembles that shown in Eggenmuller U.S. Pat. No. 4,046,069 is disclosed. In the Johnson et al machine the teeth carried on the rotor or drum are disposed on the drum in randomly located groups. The feed is forced through a generally trapezoidally-shaped (in cross-section) compression tunnel, and from this, into the storage bag. A feeder roller is rotated in the bottom of a hopper in which it is located so as to push the silage rearwardly in the machine and into the tooth-carrying drum. A disc brake assembly is used for adjusting the resistance to cable payout from drums carrying cables extended to a backstop used to secure the flexible bag against horizontal movement. A sprocket drive is employed for driving the feeder roller, as well as the tooth-carrying drum.
Both the Eggenmuller et al and Johnson et al machines disclosed in the two above mentioned patents do not, in practice, distribute the feed stock material evenly across the full width of the apparatus, so that the bags are not completely filled, and voids and air pockets exist within the silage or feed stock material, and cause spoilage to occur at a relatively early time.
It has been generally recognized by those in the business of devising and building and using machines of the type described, that the conditions differ under which a particular feed stock charged to the apparatus may be uniformly compacted and fed in a unform and consistent fashion into the flexible bags. The realization of such desiderata depends upon the weather, the time in the season, the time at which the silage material is cut and various other factors. These variables make it difficult to always achieve consistent and uniform compaction of the silage, and complete and uniform filling of the bags.
U.S. Pat. No. 4,724,876 to Ryan describes an apparatus by which vegetative feed stock, such as silage, can be ground and then discharged in a relatively uniform fashion in and to a flexible agricultural bag. The apparatus has a housing which defines a hopper, and a passageway is located between the hopper and a rotor which is rotatably mounted in the apparatus for advancing the feed stock from the hopper into the bag. A screw conveyor, or auger, is mounted ahead of a press drum or rotor and functions to distribute feed stock oppositely along the length of the screw conveyor, or auger. This aids in eliminating mounding of the feed stock in the hopper. The auger, or screw conveyor, is, however, very small in relation to the size of the press rotor employed, and some difficulty is encountered in handling large amounts of feed stock and silage which may be dumped into the hopper on top of the screw conveyor at a single time. Inserts are provided on tapered walls of the hopper in order to divert the flow of the feed stock toward the central rotational axis of the press rotor, and these inserts cooperate with the rotor and the screw conveyor to prevent excessive accumulations of quiescent feed stock in the vicinity of the press rotor.
Additional patents which show machines for filling agricultural bags, and which are of the general type here described are U.S. Pat. Nos. 4,310,036; 4,308,901; 3,687,061; 4,621,666 and 4,688,480 and Canadian Pat. No. 1,243,241.